Figure 1

(Patient 4). a. Ultrasonography of the right lobe. A solid tumor. The margins are well demarcated and irregular, and the internal echo is predominantly hypoechoic and partially anechoic. Strong echoes with acoustic shadowing (calcifications) are not present. b. Power Doppler ultrasonography of the same section as in Figure 1a. Marked chaotic vascularity is predominantly shown in the intra-tumoral lesions. c. Power Doppler ultrasonography of the right internal jugular vein. A solid mass (arrows), that is, tumor thrombus, is shown as an “echogenic tongue” in the lumen. d Hematoxylin & eosin staining. Metastatic carcinoma of the clear cell variant of renal cell carcinoma and normal thyroid tissue are shown. Tissue of the tumor histopathogically demonstrates a pseudo-alveolar or pseudo-follicular structure and no calcifications.